Ball joint

I have started to overhaul the front suspension on my GTA. I have the first side apart. I mostly looks good but I thought I might as well replace the ball joints as they are fairly cheap. The top one is straight forward enough, However the bottom one is riveted to the wishbone. Simon Auto do ball joints with nuts & bolts to attach them. The questions are:

Are the old ones best removed by grinding or drilling ?

By fitting the new one with nuts & bolts, is it as strong as the original. Is it worth the hassle, seeing that it seems ok ?

Thanks

I replace these all the time and have in stock both balljoints and refurbished arms ready to fit on a service exchange basis.
You need to grind the head off the rivet on the balljoint side,then spot and drill.You don't need to go all the way through,just enough to free it off from the bearing mount plate, then cold chisel the joint away from the arm.
There's a knack but that'll only come after you done 50 or so ....
Use std washer and nylocs on the new bolts.

Thanks Lee, that's great. Nice to have expert advice before taking grinder & drill to it