As the title implies, this is not a high quality but a low cost air ride. It may not even be safe to do but has performed well for over 1000 miles now on this DelSol.
I went to the Monroe shock/strut catalog to find all the critical information about the struts and then compared them to what Monroe offered in their Max Airshock listings. I found two excellent choices from the list of candidates; the MA705 and the MA805 pairs. These are common air shocks used for load leveling and rated at 1100 lbs per pair which is about what the DelSol weighs front to back. I have used these in the past and found them to be very well made and reliable to last a long while.
There was only a very smal modification that had to be made to make these a bolt in for the rear where they are installed. The MA705 air shocks I chose are identical to the factory struts when the lower mount is added. The lower mount was made from the exact same size metal as the origonal mounts (1 1/4" x 1/4" thick strap). I hammer formed them in a vice around a 2" wide piece of rectangle tubing. The 2" inner space matches the cars bushings exactly.
I had to cut off the stud on the lower mount in order to replace it with the strap I had made. Once cut off I cleaned the paint in the area I intended to weld the stap on. You have to make sure the air fitting is pointing in the correct direction because the air shock will not rotate before you weld the strap on. Once correctly maked, you must tack weld it on and quickly quench it in water. This is VERY IMPORTANT as you can damage the air shock with too much heat and must be removed fast. After the tack is set and all things are clocked correctly, you can fully weld the strap on in four steps while quenching with water. Wire brush it, paint it, install it.
These air shocks are rated (which means there is a window of safety built into their design, greater than their intended use) at 150psi to use safely. After I installed them and filled them up for the first time it only took 90 psi to lift the car to the origonal lowered stance (2.5" lowered springs), and at 140 psi returned it to the origonal height.
These are a temporary mod to see the longevity of these in daily use as a sole means of vehicle support. I will upgrade to commercially available air struts later. This is going to be installed in stages, right now they are manually adjustable with an air hose. I am installing a very nice air system right now and will update this thread with more details. A full system includes a quality compressor (Viair 480), storage tank, manifold, pressure switches, fittings, air filter (to remove debris and water), lines, check valves, control valves, regulators, gages etc.. This is a costly system when designed correctly and intended for daily use. Cheap components will not last so don't bother wasting money on the cheap compressor. This system will also allow me to add an air horn and other accesories powered by air. This is how it's going so far.

 

any pictures of the car?

 

here are a couple set low. I added the air struts to support a bass installation with amp and full size spare. The TEIN springs were too low with the additional equipment so I wanted to try this out. I will replace them after the compressor and other stuff gets in first.

 

any frame notching required?

 

My only concern would be that the entire load of the rear of the car is now supported by the small rubber bushing that would normally only isolate the shock. It may not make a difference but normally the load of the car is supported by the area around the shock at the "top hat". I wouldn't say it's dangerous though, worse case the rubber bushing fails and falls out then start makes a clanking noise alerting you of a problem.

 

Been driving this nearly everyday for a couple months and no concerns. Checked in after each oil change and looks fine overall.

I have not had to add any air since the first fill up so I must have gotten a good set.

I had the trunk filled with a motor once (B series) and drove it without issue. Surly not the best airride available but has worked well none the less. Now that I have my rear sub installed with the amp (75lbs), I will be installing the air compressor and components for adjustability.

 

You should add a large flat washer under each tophat bushing so that in the event that the bushing fails the car will still be supported. Nice DIY none the less.
This is off topic but I like the spare tire sub enclosure.