Holley makes an adapter plate to change from a Rochester Quadrajet (our Solex'es are a licensed copy of the Qjets) to a GM TBI unit. The rear mounting holes need to be re-drilled on their adapter but other than that it is a straight bolt on unit.

Any GM 2bbl TBI bolts right on the adapter, slip the riser stack on the TBI unit and plop the stock air cleaner on the riser.

Somewhere, buried in one of my postings on FI conversion, I've listed the part number from Holley.