Depending on which stock model and material (laminate?) just be aware that with a typical FT scope on top you can expect the TX rig to weigh north of 15lbs!, you might want to consider this prior to adding more weight with an adjustable forend.
Other than for extreme elevated targets it is unlikely to bring much benefit over a standard up/ down adjustable hamster (e.g, on Gary's GP stocks).
Just a thought...
The Auld Alliance