I'm new to coil overs, but I'm going with them for the front.
Coil-Over MountsSold in sets of 2. These plates built and designed by SSM offer the perfect landing for your coil-overs. The new muscle car coilover conversions offered by the spring companies use the lower shock t bar mount to support the entire weight of your car on a spot that was not...
southsidemachineperformance.com
I'm using these reinforcement plates with stock lower arms and TRZ uppers.
Regarding the coilovers, you can get a spring that goes in the stock spring pocket in the frame that won't require modification to the shock bolt area. Here is a kit that UMI sells :
https://www.umiperformance.com/home...ront-coil-over-kit-double-adjustable-bearing/
I can't say this style spring is better, good or bad. But I'm about to find out lol.