What parts are you using from what vehicle? Specifically the Power Steering Pump and Tensioner/Alt Bracket/Heater components?
The tensioner bracket is different on the GTP, very similar but not identicle. I didn't realise there may be a different in Power Steering Pumps either, that said, both of these assemblies obviously mount to the same holes on the engine.
In case you have mixed components, I would suggest you use the Bonneville Tensioner Assembly and Power Steering Pump if you're not already. But I'm sure this is the root of your problem, you must be using the GTP Tensioner Assembly, right?
40th Anniversary Edition
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FWI | 4" Intake | LQ4 | N* TB | Custom TB Adaptor | Ported SC | 2.8" Pulley | Custom Intercooler | Ported LIM | Custom Ported Heads | 105# CC Springs | Modded Retainers | Oil Restricted Push Rods | CC OE-R Lifters | XP Hot Cam | TOG | HF Cat | 2800 ST | 3.29 Gears | DHP PowrTuner | LC-1 Wideband | Engine now retired |