Subframe connectors?

when we put in the 416 we put them in right away...didnt know what times I would be doing..but to be safe we put them in...I had bought the bolt in ones from Mancini Racing...but we welded thenm in as well...and did not have to do any floor cutting on my Duster...now she is stiff like good wood and no more flex...glad I put them in..the car leaves hard...have to get her to the track when it gets warmer...