Hi and welcome to this forum, there are a few kiwis lurking about here, a valuable site for construction information, as for locating the book try this link,
http://www.fishpond.co.nz/advanced_s...own+sports+car may be helpfull. Another usefull site is this kiwi one
http://www.lotus7.co.nz/forum/ ,seems to be quite a number of guys in the Christchurch area. Sometimes Sierra's come up on Trademe so worth having a look there.For my build Im using sierra diff axles and hubs,and steering column, 4age 20valve Black top with T50 box,mk3 cortina front uprights hubs and stubs. Good luck with build.Cheers Brendan.