Had to do all 8 of our 99 same company. I did them and it not hard. This was 4/5 years back and still look new.
http://www.dkhardware.com/ This is where I purchase the stuff.
you want to search for Super Spacer and Super Spacer Sealant
The spacer comes in 66 foot roll and around $50 per roll
The Sealant comes in a regular caulk tube. Around $10 per tube
It takes about one tube per window. For my 8 windows I need just under 2 rolls. You want to read up on the CrLaurence products at their web site.
http://www.crlaurence.com/ Pm me if you want the steps
Gene