Stretching a new belt might take a WHILE---so take the belt off, position the alternator, and see what length NEW belt you will need. Make sure the alternator will clear other things, like the cowling, baffles. Sometimes changing 1 accessory can create several other issues.
Tom Swearengen, TS Flightlines LLC
Teflon Hose Assemblies for Experimentals
Proud Vendor for RV1, Donator to VAF
RV7 Tail Kit Completed, Fuse started-Pay as I go Plan