There is no need to modify the valve just insert it between the two valves. It comes with two longer stainless steel bolts to replace the original. It is very easy to install just four bolts to remove the front fender and only takes about 10 minutes and can be removed at anytime. The item "ANTI DIVE SHIM for GL1800 GOLDWING No more blown fork seals MADE IN THE USA" is in sale since Friday, August 28, 2020.
This item is in the category "eBay Motors\Parts & Accessories\Motorcycle Parts\Brakes & Suspension\Other Brakes & Suspension". The seller is "depew_industries" and is located in Lancaster, New York. This item can be shipped worldwide.