Here is the same quote, updated for a street/strip application, which applies to the OP:

Strange sheetmetal housing with ends welded on - $525.00
Strange Pro HD center section with a spool, 4.10 gear, and billet yoke - $1245.00
Upgrade to S-Trac differential $805
Strange axles with bearings and 5/8 studs - $515.00
TOTAL $3090