If its your first rally car i would look at a bolt in ,because chances are you will have a excustion in to the forest at some time.
Not putting a mocker on you but ive seen it happen a lot.
Then with a bolt in at least you can transfer it to a new shell.
Weld in are the best but you need to get it done by a pro.
I think bonds bolt in are around 1300-1400 approx.A mate of mine just got his rex back from bonds ,weld in seam welded,plated etc 8500.
But it is a work of art .
I would strongly advise not to weld it in your self if you go that path ,because it will be a hassle when it comes to getting it logbooked.
I would seam weld strut towers add brace ,reinforce rear spring hangers as well ,then get out there have some fun .
rob