D15B Complete Is For Like 45k Complete With Wiring ECU And All.......!!
Well You Have D16 ECU And Loom....I Believe Its Important Item......!! Can't Say About Block And Head.......!! Better Gave It In Replacement As You Getting The Good D15B......! No Use To Keep It........!!
In Case...You Can Use Your Wiring And ECU And Gearbox....!
Get Good D15B Assembly Complete With Head And All......!
I Am 90% This ECU Can Work.......On 3 Stage VTEC....It Get Changed....With D15b 2 Stage...It Can Work Fine I Think....!!
Getting Just Assembly Is Cheap Without Gear And Wiring ECU.......Give This Block Head And Get D15B VTEC one....!!
If Your Block Is All Good..Then Also You Can Get VTEC Head For It......!! Remove This One And Get VTEC Head On It....I Am Sure There Not So Diff Swapping VTEC Head On This Block....Since Its Also D15B....!That Can Also Works (y).....But In Case Block Is Perfectooo.......
Else Its Useless....!
Make Sure 1st In All Cases.....This ECU Works With It......!! Else You Also Need ECU...But I Think Your OLD D16 Also Got VTEC So It Supports VTEC......
Best Of Luck
Regards