I'll reply here (not sure why you posted 2x, but feel free to delete the other thread so we're not jumping back and forth)...
I suggest spending the $25-ish for the A/C delete idler pulley (Dorman# 34195 at whatever store/vendor you find the best deal). Keeps the stock belt, and installs in ~5min after the compressor is gone. Ran this on my old 1998 Grand Prix for a few years when I didn't want to chase the A/C leak (now I'm more into A/C as I've lived further south).
If you remove the A/C compressor, you'd have to move a lot of things around to route the belt right. If you're doing something very custom outside of a normal 3800 vehicle, moving the alternator, P/S pump, tensioner, and idlers to work with the WP and crank would be something you'd have to line-up and measure yourself.
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