GT40X kit info?

Cant find anything usefull on fordracing.com these days. This kit
comes without roller lifters, with 1.7" roller rockers.

First off, just curious if it will give significant gains on the low
end. Throttle response, torque, etc. Will the high lift be too much
for a smooth running street car?

Standard length pushrods?

Work with stock pistons for 89 GT ?

Thanks for any info.

http://www.latemodelrestoration.com/iwwida.pvx?;item?item_no=LRS-6049B-K%20%20%20%201&comp=LRS
If link doesnt work its under mustangparts\underhood\cylinderheads
\topendkits
found these guys through MM & FFs magazine.