I'm in the process of trying to mount a donor engine (1.7) into the hole where my 1.8 was. The 1.7 had a tail shift mounting bar, I'm trying to figure out if there's a bushing that mounts between the sideshift mounting bar and the engine? The bolts in the old bar are too large to fit into the holes on the engine.
Should I just drill the bar for the larger bolts? it appears the bolts will fit the case.

You need the mounts, both the metal brackets and the rubber isolaters, to mount the earlier engine to the car if you're gona use the side shifter trans. No way aroungd it. the Cap'n

Metal brackets and isolators? The fire was bad, but I didn't see these melted. Any part numbers or pictures?

When they went from the tail to the side shifter mounting bar, they swapped where the rubber mounts go. On the tail shifter, the rubber mounts are on the body, and the bar is solidly mounted to the engine. On the side shifter, the rubber mounts go between the engine and the bar, and the bar is solidly mounted to the body.

You'll need: the side-shift mounts that bolt to the engine, the side-shift rubber bits that bolt to those mounts and the bar, the bar, the solid mounts at the body, and the bolts that connect the bar to the body. None of the tail-shifter stuff can be reused. You also need a complete shift linkage up to and including the shift lever itself. Buy new shift bushings while you're in there.

There are more notes on my blog, with not enough pictures, of how to do this.

Fortunately I have most of the parts. The side shifter was in the car before the fire the rubber mounts are the only thing I should need.
Mine were burnt beyond recognition.