Hi Shaun,
Good post , nice and clear with all the needed info.
You're on the right track.
D/l this .zip, rt click it Properties>Unblock> Apply>OK .
View attachment 48712
Extract the .zip and copy bootsect.exe into your C:\windows\System32 folder.
Open an elevated command ( type cmd in start search box - when the black box pops up - rt click it and run as admin.)
Type the following , and press enter after each line:
bcdboot c:\windows /s c:
bootsect /nt60 c: /mbr
diskpart
sel vol c
act
sel vol f
inact
exi
close cmd prompt. Restart. You're good.
You might want to go into Bios and set Disk 0 as first HD in Bios boot order - not essential.
You need to keep the C letter for the 7 partition ( which you want to do anyway).
The others you can change as you like. In Disk Management, Rt click the one you want to change and select "Change drive letters and paths".