Motor plate question

A little info: Using a motor plate on my 512 Victor headed engine in my 72 duster with 2 inch Tti headers and I have to raise engine about a 1/2 inch higher to fit. question 1). Can I just bolt the motor plate to the uni frame as I don’t want to weld it in as the engine bay is all painted and pretty. 2) if I can bolt it in how would you recommend doing it. 3) the motor is about 685 hp with maybe 150 shot down the road. Thanks guys
https://arengineering.com/products/bracket-kit-motor-platesYou
You can use these & make spacers that go on your frame.
Mancini and Hughes sell them.