1) Bolts are not supplied with top mounts Dan so it may have been a mis match or something YOU used that maybe caused them to snap ? All the bolt is used for is to hold the top mount in position not to take any load And as those are not supplied why knock the top mount ??

2) Cut and shut welded is one of the reasons why I have moved on to the the fully CNC machined single piece solid billet bar type. That costs us more in the long run but it will bend way before it would ever get the chance to snap. There is no welding to break.

3) Doh an ARB wont STOP body roll, that is down to a combination of springs and dampers. I'd guess your Konis were an unspecified road set-up ? If your mate builds rally cars he shouldnt be building them to road spec unless its going to be a road rally car, in which case sometimes those mods are bend