SETUP ROUTING

I will give this a whack..
Connect your four delta outputs to inputs E through H on your Tascam. Both are 1/4. This keeps your first four inputs be available for XLR/1/4 equipment (Sound modules? Mics? Effs?)The stereo outs on the Tascam would connect to your inputs 1 and 2 on your Delta. You will need a 1/4 to RCA male to male cable for this. The Tascam 1/4 monitors outs are intended to send your music to the performers (Other wise connect this to your playback amp in your monitoring room).
For the sake of simplicity and the amount of information you provided this is all I can say for now. But I have questions to expand my answer. Which unit (Mixer/Computer) will be master clock? Which unit will be actually recording Tracks? What software on the computer are you using? (Reasons? Fruity? Sonar?) Any effect processors? And synth? (Outboard gear or software?) With that last question being asked I have to included "Is there any MIDI?" Those answers would be instrumental (no pun intended) in me providing more assistance.

Hope this is helpful!