Will this obd1 5.7 tbi intake bolt on to the obd1 4.3 tbi?CHEVY C/K 1500 2500 3500 AIR INTAKE 1992 1993 1994 1995 | eBay

Will either of these obd2 4.3 headers bolt up to the obd1 4.3 heads and stock ypipe/cat(or the Magnaflow ypipe/cat)?
PaceSetter 70-1321 Painted Black Shorty Header 96-99 Chevy GMC Truck w/ 4.3L V6 | eBay
OBX 96-01 CHEVROLET S10 PICKUP 4.3L V6 Exhaust Header | eBay
MagnaFlow Catalytic Converters - 49-STATE & CANADA Catalytic Converters For Trucks, Suv's, American Muscle, Diesel, & Sport Compact Vehicles

My brother allready has a k&n replacement filter in the stock airbox, but he wants an intake like I linked above, with the round tbi adapter and the tube and cone filter (I have a k&n cone I would put on there instead of the blue filter) that he plans to build a heatshield or airbox around, kind of like the Airraid or Volant intakes.

The stock cast exhaust manifold seems to have a little crack in it on one side, so we got on ebay and he wants one of those shorty headers, and wants to replace his old oem cat with the Magnaflow. He doesnt want LT headers or custom cat setup, he wants a bolt on short header and bolt on cat section like linked above, but I am unsure of fitment. The 95 5.7 tbi and intake system look identical to me, so Im thinking the 88-99 v8 tbi intake above would fit the 95 4.3 tbi perfectly. Im also thinking the obd2 headers above would physically bolt up just fine, but may need to block off an air injection port or plug an o2 bung? Im just looking for clarity as to if these will physicaly bolt on...

 

i got a 95 v6 vortec and it keeps giving me code 42 electtronic spark timing (EST) circuit grounded what do i need to do to fix this asap