Do your self a favor before installing the windlace. Cut a piece off the end of it (about an inch) and use it to slide thru the channel. This will help you find any tight spots, you can then open those spots up making the install much easier.
Start by sliding the wind lace thru the upper retainer, leaving enough to go down the front and back. Then do the fore mentioned. Use soapy water to help it slide thru, especially past the dash, that's the hardest part.
Yes, your fingers will have cramps so a pair of pliers will help pull as you push with the other hand.
Good Luck,
Wilbur