If you can find someone around with a DRB III and the right adapter cable you can run some tests on the car. My mom's 94 was having some misfire issues and with the tool you can individually command each coil to fire to see if the problem is somewhere in the ignition system or somewhere else. I think you can also individually fire injectors, but have to be careful with that as it will flood cylinders if you aren't careful. The tricky part with the earlier cars is they have two engine computers. Dodge didn't have one that had enough channels to fire 10 injectors and plugs, so they split it up between two computers. If I remember correctly one fires all the injectors and 2 of the coils and the other fires the other 8 coils. So even if your mechanic is telling you you need a new computer, you might need to be careful about which one you are replacing depending on what the issue really is. Dan Lesser of Viper Specialty is really well versed in the electronics on Vipers, so you might reach out to him. I'm guessing he might either have a computer handy or could possibly fix yours for cheaper.