if you are planing on chucking the stock pieces in the garbage like i did, you can rip all that stuff out and have a new one in, in about 30 minutes. Firewall adjuster too?? add about another 20 minutes. Just make sure you know what you are looking at before you start cutting and ripping. hehehe.
More of a 'pain' than 'hard' - depending on your size, it may be difficult to get under the dash to pull the stock quadrant and replace it with the aftermarket. I'm 6'2" round and fifty years old and I still managed it OK. It's a quite worthwhile mod.
take your drivers side seat out...just for bolts and a plug and it's out. It will make your life much better during this install.
The firewall adjuster is a piece of cake to install, but the quadrant is a bitch. Now it is not hard to do, just annoying cause it won't want to come out. A few curse words and a punching bag will be very helpful here.
I installed the Steeda quadrant and firewall adjuster. The instructions sucked, the plastic clip closest to the firewall is a DOG to remove as the spring is wraped around the support - you will see what I mean... It is hard to get under the dash with the seat in, but it can be done. I reused the stock cable, and trashed the Steeda cable, as the stock looked much better - I say keep the stock cable. It is very easy to remove the clutch cable from the shifter fork on the transmission. The bulbous part of the stock cable at the stock firewall holder must be cut off with a hacksaw, or other similar device, if a Steeda firewall adjuster is used - the instructions are not clear about that either... Steeda did not provide me with a brass clutch cable adapter, and when I called them they say it isn't needed. I caught up with some other local 03 Cobra guys who had the Steeda firewall adjuster, and they got that brass bushing, and it is indeed needed.
Bottom line - can be done easily by someone with limited mechanical abilities, it is a worthwhile mod, and buy it from someone other than STEEDA IMO!