Some of them come out very well. I have several old Jag's so I follow the community pretty close. The Jag community seems much more accepting of the swaps than others for some reason. I get it with these E type V12's, it's becoming a nightmare to get good parts. But I really do want to keep mine Jag if I can, but I do understand.
https://www.jaguarforums.com/forum/e-type-xk-e-59/xke-resto-mod-project-v8-196591/