diff --git a/ChainBoot.py b/ChainBoot.py
index 740e94a..64728b6 100755
--- a/ChainBoot.py
+++ b/ChainBoot.py
@@ -286,7 +286,7 @@ while 1:
                     # break # wait for another request, you mofo!
 
         elif boot_type == 128:
-            boot_seq, boot_blkoffset, boot_blkcnt = struct.unpack_from('>HLL', data); boot_imgname = b'A608.dsk'
+            boot_seq, boot_imgnum, boot_blkoffset, boot_blkcnt = struct.unpack_from('>HLLL', data); boot_imgname = b'A608.dsk'
             boot_blkcnt = min(boot_blkcnt, 32)
             boot_imgname = boot_imgname.decode('mac_roman')
             for blk in range(boot_blkoffset, boot_blkoffset + boot_blkcnt):
@@ -300,7 +300,7 @@ while 1:
                 (MCAST_ADDR, MCAST_PORT))
 
         elif boot_type == 130:
-            boot_type, blk, seq, hunk_start = struct.unpack_from('>BBHL', whole_data)
+            boot_type, blk, seq, boot_imgnum, hunk_start = struct.unpack_from('>BBHLL', whole_data)
             if seq != buf_sequence:
                 buf_sequence = seq
                 buf = bytearray(32*512)
diff --git a/ChainLoader.a b/ChainLoader.a
index 79feaae..7561e6f 100644
--- a/ChainLoader.a
+++ b/ChainLoader.a
@@ -173,6 +173,7 @@ DrvrBase
 DrvrName    dc.b    8, ".netBOOT", 0
 
 g
+gImage      dc.l    0               ; "configuration mode" by default
 gMyDCE      dc.l    0
 gExpectHdr  dc.l    0
 gProgress   dc.l    0
@@ -243,6 +244,7 @@ DrvrSendRead
             lea     gQuery,A2
             move.w  #$8000,(A2)+                    ; Means a polite request
             move.w  gExpectHdr+2,(A2)+
+            move.l  gImage,(A2)+
 
             move.l  $28(A0),D0                      ; [ioActCount (in bytes)
             lsr.l   #4,D0
@@ -260,7 +262,7 @@ DrvrSendRead
             clr.w   (A2)+                           ; WDS+0: reserved field
             pea     gAddr
             move.l  (SP)+,(A2)+                     ; WDS+2: pointer to address struct
-            move.w  #12,(A2)+                       ; WDS: push pointer/length
+            move.w  #16,(A2)+                       ; WDS: push pointer/length
             pea     gQuery
             move.l  (SP)+,(A2)+
             clr.w   (A2)+                           ; WDS: end with zero
@@ -333,6 +335,7 @@ DrvrSendWrite
             move.b  #$82,(A2)+                      ; Means a polite request
             move.b  D1,(A2)+                        ; nth block of this chunk follows
             move.w  gExpectHdr+2,(A2)+
+            move.l  gImage,(A2)+
             move.l  D0,(A2)+                        ; first block of this chunk
 
             lea     gWDS,A2
@@ -340,7 +343,7 @@ DrvrSendWrite
             pea     gAddr
             move.l  (SP)+,(A2)+                     ; WDS+2: pointer to address struct
 
-            move.w  #8,(A2)+                        ; WDS: push length/ptr of header
+            move.w  #12,(A2)+                       ; WDS: push length/ptr of header
             pea     gQuery
             move.l  (SP)+,(A2)+