apple Lisa2. One working!! - one to go?

I am, as ever, in the wrong country. I've never actually seen a Lisa, and you seem to ahve access to 4 of them... I would think it's safe to put untested ICs into your machine, but puting anyting into a machine whioch could have PSU provlems seems to be a little risky... However, as (presuambly) you don;'t know these spare chips atr good, if the machine still dcesn't work, you dont; know if the problems is somewhere else entirely, or it is the ROM 9say), but you've not fitted a good one. I thought the PSU schematics were available. A lot of faults could be _rpeaired_, it's not that complex a supply (althogh SMPSUs are paerhaps not that pleasant for beginners to work on, thay have a lot of live circuitry ('live' as in 'directly connected to the mains), which will giee you a very nasty shock (at best [1] if you do the wrong thing. Oh, and making a mistake can also result in lots of expensive power transistors failing. [1] At worst you won't feel a thing. Ever again. However,m if you want to have a go at fixing the dead PSU, I cna cuggest so things to do there too. Most of which are done with the PSU unplugged -tony