Corsa-B.uk - Vauxhall, Opel and Holden Corsa B Owners Club

hi, new to the forum, was wondering if anyone can help me out. i'm going to be converting my c20xe nova to twin 40/45's and would like to know what i need to do in the way of wiring, jetting etc. i know i need to change from d.i.s. to distributor and use new inlet manifold but what do i do about wiring? have starter and alternator wiring done but do i still need to run an e.c.u.? and if so do i need to change my harness and e.c.u. to the earlier distributor type? cheers, alan