i have a 79 seville with the efi oldsmobile 350. The problem is that i replaced the thermostat and, unfortunately, the thread on the intake on the right side was stripped. the bolt wasnt unscrewed in years. Any suggestions on a fix besides a longer bolt with a washer?

Install a Heli-coil repair kit. Or retap one size larger and replace the bolt with a threaded stud and nut, Then from now on, you're not unthreading a bolt from aluminum.

Helicoil