Finally, the instructions for the rear strut conversion.

           1991 Isuzu Impulse RS Rear Strut Conversion

For this conversion you will need the original rear struts from the RS
and new front strut cartridges for an '88 MR2. Different struts are
available. Anywhere from Koni full adjustables, Tokico, KYB to cheap OEM
type. I used Koni adjustables.

1) Cut the original strut housing right below the top weld mark. Cut all
the way around the strut and remove all the internals.

2) Use a 1 1/8" hole saw and cut a hole centered in the bottom of the
strut housing. The new cartridge will sit on the lip that is left on the
bottom. Make sure the cartridge is centered on the lip.

3) A new threaded tube is needed. Inside diameter is 1 25/32". It's
available at Carrera among other places. Also get the corresponding top
nut.

4) Ream out the hole in the top nut so that it will bottom out on the
outside cartridge housing (not the inside lip near the shaft).

5) Slide the new tube over the original strut housing. Make sure the
length is proper before welding the tube to the original housing. The
top nut should not bottom out completely to the tube with the cartridge
installed. There should be a gap of about 1/8" between the nut and the
tube. Weld the tube to the original housing.

6) Install the new cartridge and tighten the nut.

7) Install the plastic washer that comes with the cartridge above the
top nut.

8) Cut the largest ring off the bump stop and install what remains on
top of the plastic washer.

9) Use a 19/32" drill bit to enlarge the hole in the top spring
retainer. This hole will need to be elongated to fit over the
corresponding section on the cartridge. A dremel tool works well. Be
careful not to oversize this hole. It must not be able to slide all the
way down the shaft. It needs to be very snug. Reinstall the top spring
retainer.

10) Using the same 19/32" bit, enlarge the hole in the top mount.
Reinstall the top mount.

11) Use washers or  appropriate spacers next so that the nut holds down
the top mount. I had to use 5 washers.

12) Use the same 1 1/8" hole saw to drill a hole in the seat belt mount
bracket  just above the top strut mount in the car. This will provide
access if you're using an adjustable strut.

13) Reinstall the strut.

If you have any questions or comments, just email me.

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dgrubbs at webtv.net