One musician started the electric violin in rock music. The very great JeanLucPonte. I saw him live with the Mahavishnu Orchestra w/ John Mc somebody who played a double neck quitar.
Jean Luc Ponty is indeed a mesmeric performer who came to rock via the Classics and then Jazz in the late 60's. Arguably some of the blues / jazz violinists who who had been playing electrified style violins ( like Sugercane Harris and Michael White ) predated Ponty in taking the solo violin to the front of the stage. Michael White for example was laying down some interesting work in this line in the mid 60's. His work with John Handy, though recorded over 35 years ago is still every bit as inspiring.
The guitarist you refer to is John MacLaughlin, whose early work I much enjoyed and particularly liked his work with Joe Farrell, especially 'Follow Your Heart' with the amazing Tony Oxley on drums. Worth hunting for.
Incidentally Ponty put down an album with Al Di Meola and Stanley Clark, 'Rite Of Strings' I think it was called which is truly superb. The mix on this album was perfect.He needs other writers to add dimensions to his own work which can begin to sound very similar after a while. Zappa did some interesting writing for him in the late 60's.
Best regards - HS