Accessory belt profile

My '97 940 engine has the alternator in a non-standard location and I tossed the old belts so I don't know what size to order.

I've seen a couple of threads here with people saying 9.5mm belts are preferable to 10mm belts and vice versa. The sites that sell belts in 10mm increments sell different profiles of V belts like Z, ZX, SPZ. Any idea which profile I want?

Z and ZX are 6mm high.
SPZ is 8mm.
I measured various spare belts I have laying around and they are between 8 and 10mm high.

Thanks, I'll give SPZ a try.