Yep, in line fuse is best, i run mine off the yellow ign wire, earthed to the steering colomn etc. just make sure the lambda & other wires are away from the king & spark leads or you may get interference

I run mine through the drivers side.... Also make sure you get the lamda sensor in the correct place, just before the bend in the d/p @ 2 or 10'oclock position (ie slightly facing the firewall or front of the car)
135 main is way to big, but if you aren't going to mess with the 2nd stage then it may well have to be that large to fuel top end. You want 14.5-14.8 on idle & test in 3rd or 4th gear right up to the highest point you will rev it to (ie i rev to 7-7500rpms) looking for 12-12.4 on WOT.
Ebay do mini drill sets, try to get one that goes up in smaller increments, mine goes 1,1.1,1.15, 1.2, 1.25 etc....
For 14 psi boost i reckon a 125 main with a 1mm or .9 a/c will do, without mods to the 2nd stage.
HTH
Steve